Time dependence and similarity analysis of peak value of chloride concentration of concrete under the simulated chloride environment

The appearance of peak value of chloride concentration and convection zone is a typical characteristic of concrete exposed to a dry-wet environment. It is necessary that the combined process of diffusion and convection should be taken into account in analyzing chloride ingress into non-saturated concrete. Since the significant effect of ambient chloride concentrations on the accumulated process of the peak value of chloride concentration, field environment test and accelerated simulated experiment have been employed to investigating the time dependent characteristic and similarity of the peak value of chloride concentration of concrete. In addition, two indicators (ratio of concentration difference, KcΔ and ratio of concentration, λcmax) were proposed to obtain their correlation of peak value of chloride concentration. Results indicate that under the field and simulated environment, the peak value of chloride concentration Cmax increases with the exposure time generally within one year, regardless of the W/C ratio. Besides, there is an obvious acceleration effect of the simulated experiment, by using the peak value of chloride concentration with exposure time of 120 d under the simulated environment, we can obtain the peak value of chloride concentration of concrete with different W/C ratios with an average exposure time of approximate 360 d.